These great silver beads are hollow with an opening that you slip over your crimp. Use beading pliers or your regular pliers to gently squeeze the cover closed. You will end up with a crimp that is hidden under a 3 mm silver bead making a very tidy finish. As the crimp is covered you won't get scratched by a rough edge either ! These are a better design than previous crimp covers as the silver or gold doesn't flake off. 20 per pack